There is an urgent need to develop a totally electric car as one of decisive factors in preventing air pollution due to motorization. With the understanding that conservation of the natural environment is a big issue in the 21st century, the inventor of the present invention started the development in 1980s and is yielding results.
Meanwhile, the inventor of the present invention has already proposed an electric car having a structure, as one of ideal structures, including an in-wheel drive system, a battery built-in frame (BBF) having a battery built under the floor thereof, and tandem wheel suspensions, each having two separate front and rear wheels mounted thereon in place of one conventional wheel.
The reason for using the tandem wheel suspensions is that use of two wheels in place of a conventional single wheel improves the road holding, thereby providing a large acceleration force. Also, the car can keep running even when some of the wheels are damaged, and an input conveyed from the road surface to a car body through each wheel can be reduced, thereby resulting in higher ride quality.